correcting my questions.. ** *Can answerer add new codecs which were not present in offer to answer SDP?* *OR * *Should answerer select codecs only in offer and list formats in the same relative order they were present in the offer?* ** Thanks. - Sumin
On 3/11/07, Sumin Seo <[EMAIL PROTECTED]> wrote: > > Hi All, > > I have a question regarding on SDP offer and answer. > One of our engineers interprets rfc 3264 like below. > "rfc 3264 doesn't say that answer MUST not include more codecs which are > not in offer. > rfc 3264 also says that the answerer MAY list the formats in their desired > order of preference. > It is RECOMMENDS that the answerer list formats in the same relative order > they were present in the offer. > So, Session MUST be established as long as there is one common codec in > answer regardless of order of preference or existence of codecs not in > answer. " > > Based on his interpretation, following negotiations should work. > Offer Answer Offer Answer > ----------> ---------------> > (a, b, c) (a, b ,c) > <---------- <---------------- > (d, b, c, e, f) (b, c, d, e, f) > I did some interop tests with several carriers. As long as first codec in > answer is one of codecs in offer, calls are successfully connected. > > *Can answerer add more codecs which were present in offer?* > *OR * > *Should answerer select codecs only in offer and list formats in the same > relative order they were present in the offer?* > > > Thanks in advance. > -Sumin. > > > > > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
